Plasterer&#39;s joint rule



p 1934- w. HUTCHEON 1,972,227

PLASTERER s JOINT RULE Filed Jan. 28, 1933 if "am/rm i ZKM Z fifty/2g Patented Sept. 4, 1934 PATENT OFFICE PLASTERERS JOINT RULE William Hutcheon, Vancouver, British Columbia, Canada Application January 28, 1933, Serial No. 653,980

2 Claims.

This invention relates to a new and useful improvement in plasterers joint rules, which usually function as a hand tool under the manipulations of a skilled workman for the purpose of fabricating the surface contours of mouldings, coves, cornices and the like more difficult features of the plasterers art.

It is also especially serviceable for the mitreing of joints both exterior and interior, and in other places where manipulative skill in the finishing of plaster work surfaces, and embellishments thereto are called for. In performing the many and various operations thus indicated it has always been found necessary in the art to strike and finish such work as quickly as possible after it has been rendered, and whilst it is in a reasonably plastic condition. But with the aid of my device it now becomes possible to add the finishing touches and complete these more diificult portions of the plaster work after the drying out process has proceeded to a certain extent. is accomplished without difficulty, and also with much greater rapidity and effectiveness than when such work is performed with the ordinary tools, even if the material is in a reasonably plastic condition. So that whether operatingwithplaster under usual working conditions or when the material has been allowed to become too dry for such work, my improved joint rule enables the operator to produce more rapid and effective work than would be accomplished with the aid of the ordinary traditional tool, as commonly used for such purposes.

As the improvements I adopt consist largely in the contour of the tool the latter is more clearly described by the aid of the accompanying drawing which forms a part of this application and in which Fig. 1 is a plan view of my improved rule and Fig. 2 is a cross section thereof on line 22 of Fig. 1.

In the drawing the numeral 3'indicates the top or bottom flat surface of the rule, 4 the front edge thereof, which is smoothly sharpened to a fairly keen edge, 5 is the back edge thereof which Moreover this is left the full thickness of the material-usually of toughened steel of the finest quality. It will be noted that the tool is rhombic-shaped in general form and outline, and is preferably symmetrical so as to always present an acute-angled contour 6 to the work. It will be further noted that the back edge, to approximately half of its length, is serrated to form sharp teeth, preferably equal sided as shown at 7. In operation the tool maybe used with its sharpened edge to the surface of the work, in the usual traditional way, and immediately upon an excess of material presenting itself thefiat surfaces of the tool are reversed and the two acute-angled portions 6 are exchanged by pivoting the tool on its centre line right angular to its front edge. 7

By this movement the toothed portion of the back edge of the tool is brought in contiguity to the working face, where by suitable manual manipulation the surface is rapidly abrased to the desired form, preferably whilst the material is in a reasonably suitable condition for such operations. But even with the plaster well set and comparatively hardened such manipulative work becomes comparatively easy.

Having now fully described my said invention, what I claim and desire to secure by Letters Patent, is:

1. A plasterers joint rule comprising a flat surfaced straight edged tool of longitudinal rhombic outline and having a sharpened front edge and opposite thereto on the back thereof a square edge, said back edge over substantially half its length being serrated into sharp teeth whereby by suitable manipulation plaster-work may be readily cut or abrased as desired.

2. A plasterers joint rule comprising a fiat surfaced straight edged tool of longitudinal rhombic outline and having a sharpened front edge and opposite thereto on the back thereof a square edge, said back edge being serrated into sharp teeth whereby by suitable manipulation plasterwork may be readily cut or abrased as desired.

WILLIAM HUTCHEON. 

